A biodiesel gas-liquid coaxial industrial furnace pulsating cyclone atomizer and system thereof

Abstract

The present application relates to a kind of based on topology's biodiesel gas-liquid coaxial industrial furnace pulsating vortex atomizer and its system, belong to energy and environmental technology field.The pulsating vortex atomizer includes vortex nozzle, fuel passage, primary air inlet, secondary air inlet, secondary air vortex sheet, primary air vortex cavity, primary vortex wind passage, secondary vortex wind passage and periodic protrusion.The primary air inlet supplies air according to flow requirement, after passing through high-pressure gas passage, the airflow that is sprayed from first-stage gas atomization vortex cavity forms stable rotating flow field, then rated flow air is supplied as auxiliary gas through secondary air inlet, after passing through periodic protrusion in inlet pipe, gas vortex is generated, so that flow is always in pulsating state.Finally, gradually open fuel control valve, spray through fuel nozzle at the end of fuel passage, so that gas-liquid two-phase mixing and the breaking effect of atomized droplet is better.

Description

TECHNICAL FIELD

[0001] The present application relates to a kind of biodiesel gas-liquid coaxial industrial furnace pulsating flow atomizer and its system, belong to energy and environmental technology field. BACKGROUND

[0002] Biomass energy is the only renewable carbon source and renewable energy that can be converted into liquid fuel, without changing the existing energy infrastructure and architecture system can realize seamless energy replacement.Biomass liquid fuel with its high energy density, easy to transport and other advantages in the industrial field has been widely applied, biodiesel as the most important biomass liquid fuel, is one of the world's major industrial operation biomass energy.Biodiesel is usually prepared by different chemical reactions from waste or unprocessed plant and animal oil, animal fat etc., a typical green environmental protection energy.

[0003] The existing industrial furnace liquid fuel is mainly heavy oil or light diesel, and there is a problem of high emission of harmful substances such as smoke, CO and HC.Biodiesel is an oxygen-containing fuel, with good low-temperature performance and lubricity, high cetane number, good combustion performance, high flash point, good storage and transportation safety, etc.The promotion of biodiesel has important practical significance for improving the proportion of renewable energy in industrial furnace fuel and reducing greenhouse gas emissions.However, biodiesel has poor low-temperature flow performance, and higher viscosity and density than diesel, which adversely affects fuel injection, atomization and evaporation characteristics, causing unstable flame combustion and increased pollutant emissions in the furnace.Therefore, the spray of alternative fuels in industrial furnace burners is crucial.Therefore, the configuration and system of the atomizer are explored to determine the mixing process of the spray and air and analyze the characteristics of the spray, which is the key to achieving optimal fuel atomization and reducing carbon emissions.

[0004] Patent application No. 201710759777X, discloses a kind of industrial furnace high-efficiency atomizing burner based on high-viscosity biomass fuel oil.The burner fuel oil passage, high-pressure nitrogen passage, high-pressure oxygen passage are concentric, three-layer cavities from inside to outside, fuel oil passage one end is equipped with fuel oil inlet, the other end is equipped with fuel oil nozzle, high-pressure nitrogen passage one end top is equipped with nitrogen inlet, high-pressure nitrogen passage other end end is equipped with first-stage nitrogen atomizing swirl vane, high-pressure oxygen passage one end top is equipped with oxygen inlet, the other end is equipped with secondary oxygen atomizing swirl vane, high-pressure oxygen passage is equipped with the mounting flange connected with industrial furnace, high-pressure oxygen passage is equipped with electronic ignition needle passing through high-pressure oxygen passage.The invention utilizes the waste nitrogen after oxygen production as auxiliary atomizing gas medium, after using nitrogen first-stage atomization, about 5cm non-combustion isolation zone is formed, ensure that oil beam will not burn in nozzle outlet, so as to solve the problem of nozzle outlet sintering and carbon deposition.But the patent application one two auxiliary gas of burner is stable flow state, the atomizing flow field of nozzle outlet is also stable flow field, there is single lack of change in spray effect, axial and radial range of spray is limited, temperature field distribution is uneven when burning;Most importantly, the generated mist drop is easy to re-aggregate into large droplet, worsen atomization effect, cause flame combustion is not sufficient, pollutant emission amount and other adverse effects is high;And to achieve the same effect under the condition of atomization, steady-state spray needs to consume more fuel. SUMMARY

[0005] In view of the problems and deficiencies of the prior art, the present application provides a biodiesel gas-liquid coaxial industrial furnace pulsed vortex atomizer and system thereof.The present application uses two-stage air atomization and pressure swirl nozzle to co-atomize, the two-stage air duct is equipped with periodic protrusions, which can always break the flow boundary layer and generate vortex, effectively solving the problem of large biodiesel atomization particle size and uneven distribution.The present application is realized by the following technical scheme.

[0006] A biodiesel gas-liquid coaxial industrial furnace pulsating cyclone atomizer, comprising a cyclone nozzle 5, a fuel channel 6, a primary air inlet 7, a secondary air inlet 8, a secondary air cyclone piece 9, a primary air cyclone cavity 10, a primary cyclone air channel 11, a secondary cyclone air channel 12, and a periodic protrusion 13; the fuel channel 6, the primary cyclone air channel 11, and the secondary cyclone air channel 12 are coaxial three-layer channels that are shortened from inside to outside in sequence, the fuel channel 6 is provided with the cyclone nozzle 5 at an outlet end, the primary cyclone air channel 11 is provided with the primary air inlet 7 at an upper end of an inlet, the secondary cyclone air channel 12 is provided with the secondary air inlet 8 at an upper end of an inlet, the primary air inlet 7 and the secondary air inlet 8 are uniformly provided with a plurality of periodic protrusions 13 inside, the primary cyclone air channel 11 is provided with the primary air cyclone cavity 10 at a terminal end, the primary air cyclone cavity 10 is uniformly provided with a plurality of cyclone high-pressure air channels from an outer surface to an inside, the secondary cyclone air channel 12 is provided with the secondary air cyclone piece 9 inside, the secondary cyclone air channel 12 is communicated with an inside of an industrial furnace 14 at an outlet end, the secondary cyclone air channel 12 is provided with the secondary air cyclone piece 9 inside, and the primary air cyclone cavity 10 is located inside the secondary cyclone air channel 12 and at a rear end of the secondary air cyclone piece 9.

[0007] The cyclone nozzle 5 comprises a cyclone core 1, a cyclone chamber 2, a spray hole 3, and a spiral groove 4, the cyclone core 1 is provided with the spiral groove 4 outside, the cyclone core 1 is provided with the cyclone chamber 2 at an end, and the cyclone chamber 2 is provided with the spray hole 3 at an outlet end.

[0008] The cyclone chamber 2 has a height of 4.4 mm, and the spray hole 3 has a diameter of 0.7 mm.

[0009] The spiral groove 4 has a screw rod length of 12 mm and a screw rod radius of 4.75 mm.

[0010] The primary air inlet 7 has a diameter of 9 mm, and the periodic protrusion 13 has a height of 3 mm; the secondary air inlet 8 has a diameter of 5.1 cm, and the periodic protrusion 13 has a height of 1.3 cm.

[0011] The cyclone air channel has 14-24 channels.

[0012] A biodiesel gas-liquid coaxial industrial furnace pulsating rotational flow atomization system, comprising an oil tank 16, a filter screen 17, an oil pump 18, a liquid flowmeter 19, an oil valve 20, a biodiesel flowmeter 21, an air valve 22, a gas flowmeter 23, a gas storage tank 24, a pulsating rotational flow atomizer 25, a laser particle size instrument 26, a high-speed camera 27 and a computer 28, the oil tank 16 is connected to a fuel passage 6 in the pulsating rotational flow atomizer 25 through the filter screen 17, the oil pump 18, the liquid flowmeter 19, the oil valve 20 and the biodiesel flowmeter 21, the gas storage tank 24 is divided into two passages through the air valve, the air pump and the gas flowmeter 23, one passage is connected to a primary air inlet 7, and the other passage is connected to a secondary air inlet 8; an observation port is arranged on a kiln wall of an industrial furnace 14, and the laser particle size instrument 26 and the high-speed camera 27 are installed on the observation port, and the laser particle size instrument 26 and the high-speed camera 27 transmit data to the computer 28.

[0013] The oil pump 18 controls the oil passage pressure to be 0.5 MPa, and the oil valve 20 controls the fuel mass flow to be 198 mL / min.

[0014] The air valve controls the primary air volume of the primary air inlet 7 to be 30 L / min, and the other air valve controls the secondary air volume of the secondary air inlet 8 to be 399 L / min.

[0015] The present application has the following beneficial effects:

[0016] (1) The primary air inlet supplies air according to the flow requirement, the airflow sprayed from the primary gas atomization rotational flow cavity after passing through the high-pressure gas passage forms a stable rotational flow field, then the rated flow air is supplied as auxiliary gas through the secondary air inlet, after passing through the periodic protrusions in the inlet pipe, the gas vortex is generated, so that the flow is always in a pulsating state. Finally, gradually open the fuel control valve, the biodiesel is sprayed out through the fuel nozzle at the end of the fuel passage, the turbulent intensity of atomization is enhanced, the gas-liquid mixing and the breaking effect of atomized droplets are better. After opening to the rated flow, the electronic ignition needle is used for ignition, the biodiesel combustion flame is observed and researched, and each control condition can be adjusted according to the actual flame in the hearth to meet the actual production demand. In order to study the effectiveness of the present burner, the atomization characteristics of the biodiesel are first studied, the spray laser particle size instrument (Winner319) is used to measure that the Sauter mean diameter (D32) of fuel particles in the oil beam after atomization of the system is 109.917 µm, the oil beam atomization cone angle is 54°-63°, the atomized particle diameter is uniform, and it is proved that the present application has good atomization effect on the biodiesel.

[0017] (2) The present application is a pulsating rotational flow atomizer. The periodic protrusions of the atomizer can cause airflow pulsation. The instability of the pulsation is conducive to breaking the surface tension of biodiesel, promoting the breakup of the liquid film, producing finer and more uniform droplets, and forming better atomization effect. Secondly, the pulsating spray is more dense and has a wider coverage, which can improve the penetration performance of the spray. Experiments have proved that the pulsating spray can also work at low flow, which is more energy-saving and consumption-reducing. Pulsating atomization can achieve better quality effect in different parameter working environments, and can be adjusted according to the combustion state in the furnace. The temperature field distribution is more uniform, so as to realize more stable and complete combustion, fast flame propagation speed, high afterburning efficiency, reduced fuel consumption, improved heat transfer efficiency, and reduced harmful gas (such as NOx and CO) emissions. BRIEF DESCRIPTION OF DRAWINGS

[0018] Figure 1 is a schematic diagram of the rotational flow nozzle structure of the present application, wherein (a) is a sectional view; (b) is a partial structure front view;

[0019] Figure 2 is a schematic diagram of the rotational flow nozzle and the primary air rotational flow cavity fluid domain of the present application;

[0020] Figure 3 is a schematic diagram of the pulsating rotational flow atomizer structure of the biodiesel gas-liquid coaxial industrial furnace of the present application;

[0021] Figure 4 is a schematic diagram of the pulsating rotational flow atomization system of the biodiesel gas-liquid coaxial industrial furnace of the present application;

[0022] Figure 5 is a biodiesel atomization form diagram sprayed out by the pulsating rotational flow atomizer in Example 1 of the present application, which is taken by a high-speed camera;

[0023] Figure 6 is a biodiesel droplet size distribution diagram sprayed out by the pulsating rotational flow atomizer in Example 1 of the present application, which is obtained by a Winner319 laser particle size instrument.

[0024] In the figure: 1-rotational flow core, 2-rotational flow chamber, 3-nozzle hole, 4-spiral groove, 5-rotational flow nozzle, 6-fuel passage, 7-primary air inlet, 8-secondary air inlet, 9-secondary air rotational flow piece, 10-primary air rotational flow cavity, 11-primary rotational flow air passage, 12-secondary rotational flow air passage, 13-periodic protrusion, 14-industrial furnace, 15-spray, 16-oil tank, 17-filter screen, 18-oil pump, 19-liquid flowmeter, 20-oil valve, 21-biodiesel flowmeter, 22-air valve, 23-gas flowmeter, 24-gas storage tank, 25-pulsating rotational flow atomizer, 26-laser particle size instrument, 27-high-speed camera, 28-computer. DETAILED DESCRIPTION

[0025] The application will be further described in conjunction with the drawings and specific embodiments. Embodiment

[0026] As Figures 1 to 3 shown, the biodiesel gas-liquid coaxial industrial furnace pulsating swirl atomizer comprises a swirl nozzle 5, a fuel passage 6, a primary air inlet 7, a secondary air inlet 8, a secondary air swirl vane 9, a primary air swirl cavity 10, a primary swirl air passage 11, a secondary swirl air passage 12 and a periodic protrusion 13; the fuel passage 6, the primary swirl air passage 11 and the secondary swirl air passage 12 are three coaxial passages shortened from inside to outside in sequence, the fuel passage 6 is provided with the swirl nozzle 5 at the outlet end, the primary swirl air passage 11 is provided with the primary air inlet 7 at the upper end of the inlet, the secondary swirl air passage 12 is provided with the secondary air inlet 8 at the upper end of the inlet, the primary air inlet 7 and the secondary air inlet 8 are both uniformly provided with a plurality of periodic protrusions 13 inside, the primary swirl air passage 11 is provided with the primary air swirl cavity 10 at the end, which is communicated with and wraps the outlet of the swirl nozzle 5, the primary air swirl cavity 10 is uniformly provided with a plurality of swirl high-pressure air passages from the outer surface to the inside, the secondary swirl air passage 12 is provided with the secondary air swirl vane 9 inside, the outlet end of the secondary swirl air passage 12 is communicated with the inside of the industrial furnace 14, the secondary swirl air passage 12 is provided with the secondary air swirl vane 9 inside, and the primary air swirl cavity 10 is located inside the secondary swirl air passage 12 and at the rear end of the secondary air swirl vane 9.

[0027] The swirl nozzle 5 comprises a swirl core 1, a swirl chamber 2, a spray hole 3 and a spiral groove 4, the swirl core 1 is provided with the spiral groove 4 outside, the swirl core 1 is provided with the swirl chamber 2 at the end, and the swirl chamber 2 is provided with the spray hole 3 at the outlet end;

[0028] The height of the swirl chamber 2 is 4.4 mm, the diameter of the spray hole 3 is 0.7 mm, the screw rod length of the spiral groove 4 is 12 mm, the screw rod radius is 4.75 mm, the diameter of the primary air inlet 7 is 9 mm, the height of the periodic protrusion 13 is 3 mm, the diameter of the secondary air inlet 8 is 5.1 cm, the height of the periodic protrusion 13 is 1.3 cm, and the number of the swirl air passages is 14.

[0029] As Figure 4As shown, the biodiesel gas-liquid coaxial industrial furnace pulsed swirl atomization system includes an oil tank 16, a filter screen 17, an oil pump 18, a liquid flow meter 19, an oil valve 20, a biodiesel flow meter 21, an air valve 22, a gas flow meter 23, a gas storage tank 24, a pulsed swirl atomizer 25, a laser particle size analyzer 26, a high-speed camera 27, and a computer 28. The oil tank 16 is connected to the fuel channel 6 in the pulsed swirl atomizer 25 through the filter screen 17, the oil pump 18, the liquid flow meter 19, the oil valve 20, and the biodiesel flow meter 21. The gas storage tank 24 is divided into two channels through the air valve and the gas flow meter 23. One channel is connected to the primary air inlet 7, and the other channel is connected to the secondary air inlet 8. The industrial furnace 14 has an observation port on its wall, on which the laser particle size analyzer 26 and the high-speed camera 27 are installed. The laser particle size analyzer 26 and the high-speed camera 27 transmit data to the computer 28.

[0030] The oil pump 18 controls the oil circuit pressure to 0.5 MPa, the oil valve 20 controls the fuel mass flow rate to 198 mL / min, the air valve controls the primary air volume of the primary air inlet 7 to 30 L / min, and another air valve controls the secondary air volume of the secondary air inlet 8 to 399 L / min.

[0031] The method using a biodiesel gas-liquid coaxial industrial furnace pulsed swirl atomization system:

[0032] (1) The air in the air storage tank 24 is controlled to enter the primary air inlet 7 and the secondary air inlet 8 through the channel and the two air valves and air pumps on the channel respectively. After the primary high-pressure air and the secondary high-pressure air pass through the periodic protrusions in the inlet pipe, a gas vortex is generated, so that the flow is always in a pulsating state. Then the pulsating primary high-pressure air enters the primary air swirl chamber 10 from the swirl air channel, realizing the mixing of biodiesel and auxiliary air in the chamber. Compared with the external mixing of the swirl plate, a higher mixing efficiency is achieved, and the subsequent atomized droplets are broken up more fully. The pulsating secondary high-pressure air is blown into the industrial furnace 14 after passing through the secondary air swirl plate 9.

[0033] (2) Open oil valve 20 and bring the kinematic viscosity to 4.05 mm. 2 / s of jatropha biodiesel enters fuel channel 6 from oil tank 16 through filter screen 17, oil pump 18, liquid flow meter 19, and biodiesel flow meter 21;

[0034] (3) Jatropha biodiesel is sprayed from the orifice 3 of the swirl nozzle 5 in the fuel passage 6 into the primary air swirl cavity 10 for the first time, and the Jatropha biodiesel is atomized into biodiesel particles, which are sprayed from the primary gas swirl cavity outlet of the primary air swirl cavity 10 into the industrial furnace 14, and the biodiesel particles entering the industrial furnace 14 are atomized again by the pulsating secondary high-pressure air in the industrial furnace 14, and the ignition device can be arranged in the industrial furnace 14 to ignite and burn the secondary atomized biodiesel particles; the secondary atomization of the biodiesel particles in the industrial furnace 14 avoids the aggregation of the droplets in the middle and rear sections of the atomized oil beam, and further promotes the breaking of the atomized droplets, and the laser particle size instrument 26 and the high-speed camera 27 are used to collect data of the biodiesel atomized particles and record in the computer 28.

[0035] In this embodiment, the high-speed camera 27 is used to capture the spray shape of the Jatropha biodiesel near the flow field, and the actual shooting picture is as shown in Figure 5 From Figure 5 it can be seen that the oil beam changes periodically, and the liquid film is uniformly distributed, and the atomized cone angle range is 54°-63°.

[0036] In this embodiment, the laser particle size instrument 26 (Winner319) is used to collect the particle size, and it is measured that the fuel droplet distribution is uniform, wherein the characteristic particle size D10=62.386 μm, D32=109.917 μm, D50=166.923 μm, D90=312.795 μm, and the droplet surface area to volume value S / V=545.865 cm 2 / cm 3 . The above is coordinated with the actual industrial furnace combustion, increases the uniform distribution of the temperature field in the furnace, and very good atomization effect is obtained through the system.

[0037] The specific embodiments of the application are described in detail above in combination with the drawings, but the application is not limited to the above embodiments, and various changes can be made within the knowledge of those skilled in the art without departing from the purpose of the application.

Claims

1. A biodiesel gas-liquid coaxial industrial furnace pulsating cyclone atomizer characterized by: The application relates to a rotary flow nozzle (5), a fuel channel (6), a primary air inlet (7), a secondary air inlet (8), a secondary air rotary flow piece (9), a primary air rotary flow cavity (10), a primary rotary flow air channel (11), a secondary rotary flow air channel (12) and periodical protrusions (13); the fuel channel (6), the primary rotary flow air channel (11) and the secondary rotary flow air channel (12) are coaxial three-layer channels which are shortened from inside to outside, the fuel channel (6) is provided with the rotary flow nozzle (5) at an outlet end, the primary rotary flow air channel (11) is provided with the primary air inlet (7) at an upper end of an inlet, the secondary rotary flow air channel (12) is provided with the secondary air inlet (8) at an upper end of an inlet, the primary air inlet (7) and the secondary air inlet (8) are uniformly provided with a plurality of periodical protrusions (13), the primary rotary flow air channel (11) is provided with the primary air rotary flow cavity (10) at a tail end of the primary rotary flow air channel (11) and the primary air rotary flow cavity (10) is in communication with a rotary flow nozzle (5) nozzle outlet and wraps the rotary flow nozzle (5) nozzle outlet, the primary air rotary flow cavity (10) is uniformly provided with a plurality of rotary flow air channels from an outer surface to an inner portion, the secondary rotary flow air channel (12) is provided with the secondary air rotary flow piece (9) in the secondary rotary flow air channel (12), the secondary rotary flow air channel (12) is in communication with an industrial furnace (14) inside the secondary rotary flow air channel (12), the secondary rotary flow air channel (12) is provided with the secondary air rotary flow piece (9), and the primary air rotary flow cavity (10) is located in the secondary rotary flow air channel (12) and at a rear end of the secondary air rotary flow piece (9).

2. The biodiesel gas-liquid coaxial industrial furnace pulsating cyclone atomizer according to claim 1, characterized in that: The rotary flow nozzle (5) comprises a rotary flow core (1), a rotary flow chamber (2), a spray hole (3) and a spiral groove (4), the rotary flow core (1) is provided with the spiral groove (4) outside, the rotary flow core (1) is provided with the rotary flow chamber (2) at an end, and the rotary flow chamber (2) is provided with the spray hole (3) at an outlet end.

3. The biodiesel gas-liquid coaxial industrial furnace pulsating cyclone atomizer according to claim 2, characterized in that: The rotary flow chamber (2) is 4.4 mm high, and the spray hole (3) is 0.7 mm in diameter.

4. The biodiesel gas-liquid coaxial industrial furnace pulsating cyclone atomizer according to claim 2, characterized in that: The spiral groove (4) is 12 mm long, and the screw rod is 4.75 mm in radius.

5. The biodiesel gas-liquid coaxial industrial furnace pulsating cyclone atomizer according to claim 1, characterized in that: The primary air inlet (7) is 9 mm in diameter, and the periodical protrusion (13) is 3 mm high; the secondary air inlet (8) is 5.1 cm in diameter, and the periodical protrusion (13) is 1.3 cm high.

6. The biodiesel gas-liquid coaxial industrial furnace pulsating cyclone atomizer according to claim 1, characterized in that: The rotary flow air channel is 14-24.

7. A biodiesel gas-liquid coaxial industrial furnace pulsating rotational flow atomization system comprising the biodiesel gas-liquid coaxial industrial furnace pulsating rotational flow atomizer (25) as claimed in claim 1, characterized in that: The system comprises an oil tank (16), a filter screen (17), an oil pump (18), a liquid flowmeter (19), an oil valve (20), a biodiesel flowmeter (21), an air valve (22), a gas flowmeter (23), an air storage tank (24), a pulsating cyclone atomizer (25), a laser particle size analyzer (26), a high-speed camera (27) and a computer (28). The oil tank (16) is connected to a fuel passage (6) in the pulsating cyclone atomizer (25) through the filter screen (17), the oil pump (18), the liquid flowmeter (19), the oil valve (20) and the biodiesel flowmeter (21). The air storage tank (24) is divided into two passages through the air valve, the air pump and the gas flowmeter (23), one passage being connected to a primary air inlet (7) and the other passage being connected to a secondary air inlet (8). The industrial furnace (14) is provided with an observation port on the kiln wall, and the laser particle size analyzer (26) and the high-speed camera (27) are installed on the observation port. The laser particle size analyzer (26) and the high-speed camera (27) transmit data to the computer (28).

8. The biodiesel gas-liquid coaxial industrial furnace pulsating cyclone atomization system according to claim 7, characterized in that: The oil pump (18) controls the oil passage pressure to be 0.5 MPa, and the oil valve (20) controls the fuel mass flow to be 198 mL / min.

9. The biodiesel gas-liquid coaxial industrial furnace pulsating cyclone atomization system according to claim 7, characterized in that: The air valve controls the primary air volume of the primary air inlet (7) to be 30 L / min, and the other air valve controls the secondary air volume of the secondary air inlet (8) to be 399 L / min.

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